Buffer



J. Tl THOMPSON.

BUFFER.

APPLICATION FlLEU APR. 28, T920.

Patented Aug. 31, 1920.

2 SHEETS-SHEET I.

2 SHEETS-SHEET 2.

Patentei Aug. 31, 1920.

\\\\\\\\\I if BUFFER.

APPLICATION FILED APII.2B. |920.

1.1. THOMPSON.

UNITED STATES JOHN TALIAFERRO THOMPSON, OF NEWPORT, KENTUCKY, ASSIGNOROF ONE-HALF T THOMAS F. RYAN,

0F NEW YORK, N. Y.

BUFFER.

Application filed April 28,

To all whom t may concern:

Be it known that I, JOHN TALIAFERRO THOMPSON, a citizen of the UnitedStates of America, and resident of Newport, in the county of Campbelland State of Kentucky, have invented new and useful Improvements Y inBuil'ers, of which the following is a specification.

My invention relates to an improved buffer adapted to cushion shocks andabsorb surplus energy, which is more specifically described herein inconnection with an embodiment particularly adapted for use as a recoilbuffer with firearms of the automatic or semi-automatic types.

Substantially all such types of arms now in use are provided with a boltor similar breech closure which reciprocates. The reciprocation iscaused in some guns directly by the breech pressure, in others by gaspressure and in various manners in other types. Regardless of the methodof accomplishing this movement of the breech block, it is accomplishedat an exceedingly rapid linear velocity, and the stopping of the memberat the end of its opening stroke, due to the inertia of the member, isOrdinarily accomplished only at the expense of a sharp jar. This jar orjolt is detrimental to all the working parts of the gun in that it is asource of wear and breakage and, moreover, it renders accuracy of iireeX- tremely difficult, especially with the lighter types of guns adaptedto be fired from the hip or the shoulder.

The breech closures are forced rearwardly either directly or indirectlyby the explosion of the cartridge and are returned to closed positionusually by some spring means, the spring means having the necessaryenergy stored therein by the opening movement of the breech. In order toform this spring means of adequate capacity to stop the rearward motiongradually and without heavy shock, it must either offer excessivelyheavy resistance or be of a length such as to preclude its use in smallarms. If suiiiciently heavy to reduce the bolt pressure with a shorttravel, its reaction is sharp and quick and the breech is closed withsubstantially Specification of Letters Patent.

Patented Aug. 31, 1920.

1920. Serial No. 377,185.

as heavy and detrimental a jolt as that which has been eliminated atvthe end of the recoil.

It is an object of my invention to provide a recoil buffer whicheffectively eliminates recoil shocks due to reciprocating breechclosures or the like, and which does not return the breech closure toclosed position with eXessive velocity. It is an object to provide abuffer of the character described which is light in weight and small insize and which may be tted in the usual receivers or recoil housingswithout the necessity of unusual space or length. It is also an ob jectto provide a buffer providing a gradual and progressive stop for thereciprocating parts and to provide in connection therewith counterrecoil means to prevent a sudden or jarring counter recoil movement. Itis an object to provide means of the character described which arestrong in construction, relatively inexpensive to manufacture, and whichwill require little attention in use. Other and further objects willappear as the description proceeds.

I accomplish these desired Objects by a buffer which supplements theusual recoil spring and continues to act in bringing the breech closureto rest and in absorbing sur plus energy after that spring has beenfully compressed, and by counter recoil means adapted to prevent toosudden return of the buffer to its normal length.

I have shown certain preferred embodiments of my invention in theaccompanying drawings in which- Figure l is a longitudinal section ofone form of my device in the normal position;

Fig. 2 is a view similar to Fig. l but showing the device in thecompressed position;

Fig. 3 is a view similar to Fig. l but of a modified form of the device;and

Fig. 4 is a View similar to Fig. 3 but of a different modified form ofthe device.

The form of the device in Figs. l and 2 is shown fitted into thel rearend of a receiver 7 and comprises a iXed member 8, movable member 9,piston lO, counter recoil cap 11 and counter recoil spring 12. The

fixed member 8 has a cylindrical body and has a circumferential flange13 which is threaded into the rear of the receiver. The rear of thecylindrical portion 8 is fitted with the plug 14 into which is screwedthe packing bushing 15 surrounding the rear of the piston stem 16. Theplug 14 is formed with a flange 17 and between this flange and thefiange 13 is fitted the packing washer 17. The counter recoil cap 11 isheld on the end of the piston stem 16 by the nut 18.

The fixed member 8 is formed with the cylindrical cavity 19 and thefrusto-conical opening 20 through its forward end. The movable member 9has the cylindrical cavity 21 therein of such size as to make a snugsliding fit with the exterior of the fixed member. The large forward endof the piston 10 is threaded into the movable member at the base of thecavity 21, the intermediate portion of the piston being frustoconical inform upon varying angles, this portion of the piston interfitting withthe opening 2O to vary its effective size during the movement of themovable member.

The front of the movable member is fitted with the impact buffer 22which may be formed of rubber, leather or similar material, and its rearend is formed with a circumferential flange 23 against which bears therear end of the recoil spring` 24. As shown in Fig. 2 the front end ofthe recoil spring is fitted to the rear of the breech closure or similarmember 25. The portion of the piston within the movable member 9 issurrounded by a series of Belleville springs 26, one end of the seriescontacting with the base of the cavity 21 and the other end of theseries bearing against the head of the fixed member 8. The cavities inthe two members have oil placed therein in such amount that when thebuffer is compressed the cavities are substantially filled as shown inFig. 2. The forward portion of the outer surface of the fixed member Sis fitted with packing rings 27 to prevent leakage of the oil. TheBelleville springs have axial openings somewhat larger than the pistonl0 through which the oil is squirted and sucked as the springs arecompressed and expanded.

The form of the device shown in Fig. 3 comprises the receiver 31, fixedmember 32, movable member 33, recoil spring 34, closure plug 35, packing36, counter recoil cap 37, and counter recoil spring 3S. The movablemember has the internal cylindrical cavity 39 making a sliding fit withthe fixed member, the cavity containing` the Belleville springs 40. TheBelleville springs are provided with slots 405 at spaced intervals intheir peripheries whereby oil is forced into and out of thesemi-inclosed space between the sets of opposed springs as they areexpanded and compressed. The cavity 39 is connected to a similar cavity41 in the fixed member by the port 42 located adjacent the lower portionof the two cavities. The rear flange 43 of the movable member isconnected to the counter recoil cap by the rods 44. The movable memberis provided with the impact buffer 45 similar to that of Figs. 1 and 2,and the fixed member with theA packing rings 46. Oil is placed in bothcavities, the amount being substantially equivalent to the spaceremaining when the buffer is in the compressed position.

As shown in Fig. 4 the device comprises the receiver 51, fixed memberl52, closure plug 53, counter recoil spring 54, guide member 55, movablemember 56, impact buffer 57, and piston The fixed member 52 and guidemember 55 are rigidly connected by the sleeve 69 having the frustoconical opening 59 therein. rlhe rearward conical portion of the pistonpasses through the opening 59 and its rear end carries the solid pistonhead 61. lts forward end passes through the perforated head or spider62. The piston head 61 is fitted with the packing ring 63.

Fitting in the cavity 64 in the movable member 56, is the series ofBelleville springs 65, which are retained in position by the reducedforward portion 66 of the piston 58, the forward end of which isthreaded to the movable member. The space between the rear face of themovable member and the piston head 61 is substantially filled with oil.The counter recoil spring is held in place by the hooks 67, and acts asa tension spring.

Considering first the form of my device shown in Figs. 1 and 2, inoperation the spring 24 is compressed by the breech closure which thenstrikes the impact buffer 22 and forces the movable member upon thefixed member. The recoil spring 24 may be made somewhat lighter thanwould be required if the buffer were not used. The force of the movingbreech closure transmitted through the spring 24 to the movable memberis preferably sufficient, however, so that the buffer member has startedto move before the breech closure comes in contact with it. Thismovement may be slight but the fact that it is in motion materiallydiminishes the meeting shock of the two parts.

As the movable member is forced over the fixed member the Bellevillesprings are compressed and the oil in the movable member is forcedthrough the orifice 2O into the fixed member. The relation between thisorifice and the piston 10 is such that the effective opening is reducedas the members move together. Since the amount of oil to be forcedthrough the orifice is substantially the same for each even increment oflinear motion of the movable member it follows that the oil velocitythrough the orifice must be increased, if the linear velocity is to Ynsbe maintained. However, the kinetic energy of the breech closure isdecreased by the amount used in forcing the oil through the orifice andthe oil velocity preferably is not increased. The most effectiverelation of the parts for stopping the bolt without jar, is that wherethe decrease in the orifice is such as to correspond to the decreasedspeed of the bolt so that the oil velocity is substantially constant andits resistance substantially uniform. The compression of the air trappedabove the oil in the fixed member also adds to the resistance of thebuffer. When the buffer is compressed the counter recoil spring 12 is insubstantially its normal position.

When the breech closure has ceased its rearward motion, the energystored in the recoil spring and buffer forces it forward again to closedposition. vWhile this motion should be sufficiently rapid to cause theclosure to carry with it a cartridge and to operate the breech lockingmeans, it should not be so excessively rapid as to impart a shock to thegun. The fact that the spring 24 is less powerful than would be requiredwithout the buffer is an important factor in decreasing the closingspeed. The relative effective return speed of the buffer is materiallyless than that of the recoil spring, so that the closure is started inits closing movement by the recoil spring without substantial directaction upon the closure by the buffer.

The buffer is retarded in its return to normal position by the fact thatthe Belleville springs are relatively slow in action, by the necessityfor the oil in the buffer to pass through a small orifice during theinitial portion of the return movement, and by the counter recoil spring12 which is compressed by the counter recoil cap 11.

The action of the form of the device shown in Fig. 3 is essentially thesame as that just described. The main difference is that there is noprovision for varying the size of the orifice between the oil chambersin the movable and fixed members and that the orifice is placed lower inthe buffer to minimize the possibility of the air in the fixed memberpassing into the movable member.

The form of the device shown in Fig. 4, differs from those of the otherfigures in that the chamber in the fixed memberl increases in size asthat in the movable member decreases, this being caused by the fact thatthe piston head 61 is rigidly connected to the movable member' and movestherewith. This piston head 61 is equal in size to the interior of themovable member. The spider 62 serves as a guide for the piston rod andas an abutment for the Belleville springs. The counter recoil spring 54Cacts by tension in this form of' the device and is entirely inclosed bythe receiver.

In all forms of the device shown the heavy Belleville springs areentirely covered by the oil in the buffer and while this is notabsolutely essential to my invention, I have found it a very desirablecombination. The Belleville springs, due to their opposed cup formationhave a squirting and sucking effect on the oil not found in other typesof springs and this action is important both in cushioning shocks and inretarding recoil.

1While I have generally referred to the liquid in my buffer as oil, itmay obviously be any suitable liquid. Should it be desired to vary theaction of the buffer somewhat in different types of guns oils or liquidsof varying viscosity may be used. Hydroline or a similar oil such asused in ordnance is particularly suitable for use in my buffer. Theaction of the buffer may be changed in an individual gun by varying theadjustment of the counter recoil cap, and consequently the action of thecounter recoil spring.

l/Vhile the embodiment of my invention which has been specificallydescribed herein is particularly adapted for use as a recoil buffer infirearms, it is to be understood that the essential features of myinvention are broadly applicable wherever means are desired toprogressively cushion shocks and absorb surplus energy and where counterrecoil or rebound is to be retarded. To enumerate another specificapplication, my invention is also peculiarly fitted for use as a shockabsorber or buffer in automobiles.

I claim:

l. A buffer for firearms or the like comprising recoil cushioning meansand mechanical means independent of the cushioning means to retard thereaction of said cushioning means.

2. A buffer for firearms or the like comprising recoil cushioning meansadapted to be reduced in length in cushioning recoil shocks, andmechanical means independent of the cushioning means to retard thereturn of said cushioning means to normal length. Y

3. A buffer for firearms or the like comprising a .Fixed member, and amovable member, means between said members adapted to cushion recoilshocks, and mechanical counter recoil means independent of thecushioning means associated with the movable member and adapted toretard the reaction of the cushioning means.

fl. A buffer for firearms or the like comprising a fixed member and amovable member, spring cushioning means between said members, a bath ofoil filling the space about said springs, and a restricted orifice foregress of said oil upon compression of said springs.

5. A buffer for firearms or the like comprising a fixed member and amovable member, Belleville springs between said members, a bath of'oilfilling the space about said springs, a chamber in the fixed member anda restricted orifice between the spring space and the chamber.

G. A buffer for firearms or the like comprising a fixed member and amovable member, spring cushioning means inclosed by the movable memberand bearing against the fixed member and a bath of oil filling the spaceabout said springs.

7. A buffer for firearms or the like comprising a fixed member and amovable member, spring cushioning means between said members, and a bathof oil filling the space about said springs, and counter recoil meansassociated with said movable member.

8. A buder for firearms or the like comprising a fixed member and amovable member, Belleville springs between said members, a bath of oilfilling the space about said springs, a chamber in the fixed member anda restricted orifice between the spring space and the chamber, and acounter recoil spring operatively associated with the movable member.

9. A buffer for firearms or the like comprising a fixed member and amovable mem ber, Belleville springs between said members, a bath of oilfilling the space about said springs, a coil spring, and meansconnecting said spring to the movable member in such manner that thecoil spring acts in opposition to the Belleville springs.

10. A buffer for firearms or the like comprising a fixed member, amovable member, a closed space formed between said members adapted to befilled with oil, an orifice in the wall of said space adapted to permitthe discharge of oil therefrom upon compression of the buffer, and meansoperated by movement of the movable member associated with the orificeand adapted to progressively vary the effective size thereof.

11. A buffer for firearms or the like comprising a fixed member, amovable member, a closed space formed between said members adapted to befilled with oil, an orifice in the wall of said space adapted to permitthe discharge of oil therefrom upon compression of the buffer, and meansoperated by movement of the movable member associated with the orificeand adapted to diminish the effective size thereof as the buffer iscompressed.

12. A buffer for firearms or the like comprising a fixed member having achamber therein, a movable member adapted to telescope upon the fixedmember, a closed space formed between the two members and adapted to befilled with oil, an orifice in the head of the fixed member connectingthe space and the chamber, and means associated with the movable memberadapted to vary the effective' size of the opening during movement ofthe member.

18. A buffer for firearms or the like comprising a fixed member having achamber therein, a movable member adapted to telescope upon the fixedmember, a closed space formed between the two members and adapted to befilled with oil an orifice in the head of the fixed member connectingthe space and the chamber, and a piston connected to the movable memberand so associated with the orifice as to diminish the effective sizethereof as the buffer is compressed.

14. A buffer for firearms or the like comprising a fixed member having achamber therein, a movable member adapted to telescope upon the fixedmember, a closed space formed between the two members' and adapted to befilled with oil, an orifice in the head of the fixed member connectingthe space and the chamber, a piston connected to the movable member andso associated with the orifice as to diminish the eective size thereofas the buffer is compressed, and spring means operatively connected tothe piston and adapted to retard the counter recoil movement of themovable member.

15. A buffer for firearms or the like comprising a fixed member having achamber therein, a movable member adapted to telescope upon the fixedmember, a closed space formed between the two members, Bellevillesprings in said space and oil filling the space about said springs, anorifice in the head of the fixed member connecting the space and thechamber, and means associated with the movable member adapted to varythe effective size of the opening during movement of the member.

16. A buffer for firearms or the like comprising a fixed member having achamber therein, a movable member adapted to telescope upon the fixedmember, a closed space formed between the two members, Bellevillesprings in said space and oil filling the space about said springs, anorifice in the head of the fixed member connecting the space and thechamber, and a piston extending from the movable member and passingthrough the Belleville springs and the orifice, and adapted to vary theeffective size of the orifice during the movement of the movable member.

17. A buffer for firearms or the like comprising a fixed member having achamber therein, a movable memberA adapted to telescope upon the fixedmember, a closed space formed between the two members, Bellevillesprings in said space and oil filling the space about said springs, anorifice in the head of the fixed member connecting the space and thechamber, a piston extending from the movable member and passing throughthe Belleville springs, and the orifice, and adapted to vary theeffective size of the orifice during the movement of the movable member,and spring means operatively connected to the piston and adapted toretard the counter recoil movement of the movable member.

18. Recoil cushioning means for guns comprising a recoil spring, abuffer having cushioning means therein, and means associated with thebuffer adapted to retard the reaction of the buffer cushioning means.

19. Recoil cushioning means for guns comprising a recoil spring and abufi'er having a movable and a fixed member and resilient meanstherebetween, Vone end of the recoil spring bearing against the movablemember and the other end being adapted to receive the recoil thrust fromthe breech closure of the gun, the recoil spring and buffer being soassociated as to permit a breech closure to contact with the movablemember during a portion of its recoil travel.

20. Recoil cushioning means for guns comprising a recoil spring and abuffer having a movable and a fixed member and resilient meanstherebetween, one end of the recoil spring bearing against the movablemember and the other end being adapted to receive the recoil thrust fromthe breech closure of the gun, the recoil spring and buffer being soassociated as to permit a breech closure to contact with the movablemember during a portion of its recoil travel, and means associated withthe buffer adapted to retard its counter recoil movement and thus tominimize the contact between buffer and breech closure during counterrecoil.

21. Recoil cushioning means for guns comprising a recoil spring and abuffer having a movable and a fixed member, a space formed between saidmembers, Belleville springs therein and oil surrounding the springs, thespace having a restricted orifice, one end of the recoil spring bearingagainst the movable member and the other end being adapted to receivethe recoil thrust from the breech closure of the gun, the recoil springand buffer being so associated as to permit a breech closure to con tactwith the movable member during a portion of its recoil travel wherebythe Belleville springs are compressed and a portion of the oil forcedthrough the restricted orifice.

22. Recoil cushioning means for guns comprising a recoil spring and abuffer having a movable and a fixed member, a space formed between saidmembers, Belleville springs therein and oil surrounding the springs, thespacehaving a restricted orifice, one end of the recoil spring bearingagainst the movable member and the other end being adapted to receivethe recoil thrust from the breech closure of the gun, the recoil springand buffer being so associated as to permit a breech closure to contactwith the movable member during a portion of its recoil travel wherebythe Belleville springs are compressed and a portion of the oil forcedthrough the restricted orifice, and a counter recoil spring operativelyassociated with the movable member whereby counter recoil of the bufferis retarded.

Signed by me at New Canaan, Connecticut, this twenty-fourth day ofApril, 1920.

JOHN TALIAFERRO THOMPSON.

